In the prior art various weight lifting equipment have been disclosed, including that in the following U.S. patents:
No. 3,346,256 to J. R. White, 10 -10-67, disclosed a guided lift bar with adjustable weights;
No. 3,948,513 to J. M. Plotenhauer, 4-6-76, disclosed apparatus with four uprights having matching adjustment holes, and horizontal members for mounting to the uprights by pins through the holes;
No. 4,252,314 to L. Ceppo, 2-4-81, disclosed a guided weight carrying bar in a frame having several uprights;
No. 4,306,715 to J. W. Sutherland, 12-22-81, disclosed a four-upright frame with adjustable height horizontal bars or side-safety-rails;
No. 4,319,747 to J. F. Rogers, 3-16-82, disclosed a form of combined apparatus for use with barbells.